chr7-44513654-GGA-G

Position:

• chr7-44513654-GGA-G

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP6 BS2

The NM_001101648.2(NPC1L1):​c.3797-7_3797-6del variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000587 in 1,611,746 control chromosomes in the GnomAD database, including 6 homozygotes. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Benign (no stars).

• Frequency:
  • Genomes: 𝑓 0.0030 (5 hom., cov: 32)
  • Exomes 𝑓: 0.00034 (1 hom.)
• Consequence: NPC1L1 NM_001101648.2 splice_region, splice_polypyrimidine_tract, intron
• Clinical Significance: Benign no assertion criteria provided B:1
• Conservation: PhyloP100: 0.781

Genes affected

NPC1L1 (HGNC:7898): (NPC1 like intracellular cholesterol transporter 1) The protein encoded by this gene is a multi-pass membrane protein. It contains a conserved N-terminal Niemann-Pick C1 (NPC1) domain and a putative sterol-sensing domain (SSD) which includes a YQRL motif functioning as a plasma membrane to trans-Golgi network transport signal in other proteins. This protein takes up free cholesterol into cells through vesicular endocytosis and plays a critical role in the absorption of intestinal cholesterol. It also has the ability to transport alpha-tocopherol (vitamin E). The drug ezetimibe targets this protein and inhibits the absorption of intestinal cholesterol and alpha-tocopherol. In addition, this protein may play a critical role in regulating lipid metabolism. Polymorphic variations in this gene are associated with plasma total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels and coronary heart disease (CHD) risk. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Likely_benign. Variant got -5 ACMG points.

• BP6: Variant 7-44513654-GGA-G is Benign according to our data. Variant chr7-44513654-GGA-G is described in ClinVar as [Benign]. Clinvar id is 3035606.Status of the report is no_assertion_criteria_provided, 0 stars.
• BS2: High Homozygotes in GnomAd4 at 5 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NPC1L1	NM_001101648.2	c.3797-7_3797-6del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000381160.8
NPC1L1	NM_013389.3	c.3878-7_3878-6del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant
NPC1L1	XM_011515326.4	c.3602-7_3602-6del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant
NPC1L1	XM_011515328.3	c.2156-7_2156-6del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NPC1L1	ENST00000381160.8	c.3797-7_3797-6del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_001101648.2	P1
NPC1L1	ENST00000289547.8	c.3878-7_3878-6del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1
NPC1L1	ENST00000546276.5	c.3659-7_3659-6del		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1

Frequencies

GnomAD3 genomes AF: 0.00300 AC: 456 AN: 152178 Hom.: 5 Cov.: 32

Gnomad AFR AF: 0.0102

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00151

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00430

GnomAD3 exomes AF: 0.000871 AC: 216 AN: 248074 Hom.: 1 AF XY: 0.000610 AC XY: 82 AN XY: 134342

Gnomad AFR exome AF: 0.0116

Gnomad AMR exome AF: 0.000723

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000900

Gnomad OTH exome AF: 0.000328

GnomAD4 exome AF: 0.000336 AC: 490 AN: 1459450 Hom.: 1 AF XY: 0.000262 AC XY: 190 AN XY: 726084

Gnomad4 AFR exome AF: 0.0123

Gnomad4 AMR exome AF: 0.000783

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.000697

GnomAD4 genome AF: 0.00299 AC: 456 AN: 152296 Hom.: 5 Cov.: 32 AF XY: 0.00306 AC XY: 228 AN XY: 74466

Gnomad4 AFR AF: 0.0102

Gnomad4 AMR AF: 0.00150

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00425

Alfa AF: 0.00139 Hom.: 0

Bravo AF: 0.00356

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:1

Revision: no assertion criteria provided

Submissions by phenotype

NPC1L1-related disorder Benign:1

Benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Feb 21, 2019

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs551386034; hg19: chr7-44553253;